Bahia Magdalena, a broad lagoon on the Pacific side of Baja California, is home to one of the world’s most robust green sea turtle populations – a source of pride among locals who lead trips to see the creatures in action. And rather than just spot them from afar, or perhaps catch a glimpse of one while snorkeling nearby, visitors can spend their vacation working directly with this endangered species while helping to preserve them.

Seven-day sea turtle monitoring trips – which include a place to sleep, boats, and meals, all run by locals – begin in La Paz, Baja California Sur, a bustling seaside city with a long malecon, or seawall. Groups travel by van across the mountainous peninsula to San Carlos for an orientation, followed by a short boat ride to Isla Conchalita, or Little Shell Island, where tents line a beach backed by lush mangroves.

A typical morning is spent putting out nets in the bay, and later, weighing, measuring, and tagging each turtle that’s caught before releasing it. All this information is added to data collected during the past decade-plus, providing policy makers with a critical picture of the health, habitat use, and migration patterns of the sea turtles.

It’s not all work, though: There are plenty of opportunities for, say, kayaking through mangroves, or a hike through estuaries looking for birds, or just relaxing on the beach while eating fresh fish tacos prepared in the camp kitchen. The group also goes out with local fishermen in pangas, the white-and-blue fiberglass boats that are common in Baja, to learn sustainable fishing techniques used in Mag Bay (such as hand-lining and shrimp trawls, which don’t drag the bottom and move slowly enough for other marine life to escape). You can also spend an afternoon exploring massive, pristine sand dunes and an endless beach littered with sand dollars the size of your hand.

More information: Trips run from October to January and March to May. [From $1,100, includes all transportation in-country, camping, guides, activities and most meals; seethewild.org]